Figure 4From: Optimizing parameters of an open-source airway segmentation algorithm using different CT imagesExample of “masking” as it appears on a sagittal slice. Half trachea label is used to turn values where the half trachea overlays to 0 HU (grey voxels). In the picture, the left part of the trachea is masked, to allow segmentation of the right lung. A closing process is also used to make sure that no spreading within the left lung is obtained.Back to article page